Antistatic molded article and antistatic coating

ABSTRACT

An antistatic molded article obtained only by coating a substrate with an antistatic paint, which antistatic molded article has smooth surface, does not deteriorate the transparency and coloration of substrate and excels in antistatic properties. In particular, an antistatic molded article comprising a substrate of complex configuration such as three-dimensional configuration having irregularity and, superimposed thereon, an antistatic layer. There is also provided an antistatic paint whose application is easy, which antistatic paint does not need any after treatment and excels in transparency, surface smoothness and antistatic properties. More specifically, there are provided an antistatic molded article comprising a substrate and, superimposed on a surface thereof, an antistatic layer from an antistatic paint containing a conductive metal oxide, which antistatic molded article exhibits a surface resistivity of 1×10 4  to 1×10 9  Ω/□ and a surface roughness (Ra) of 5 to 50 nm; and an antistatic paint for use therein.

FIELD OF THE INVENTION

The invention relates to a molded body and an antistatic coatingmaterial, which have an excellent antistatic property.

BACKGROUND ART

Recently, in electric and electronic industries of mainly semiconductorfabrication, food industries, and medical and pharmaceutical industries,contamination with even a slight amount of foreign substances such asdirt and dust is a serious issue with respect to the quality control andtherefore some processes require to be carried out in clean environmentswith scarce dirt and dust, however to keep such clean environments,generation of static electricity which adsorbs dirt and dust becomes anobstacle and accordingly articles to be used in the clean environmentsare required to have an antistatic property. Also, since electric partstend to easily cause functional breakdown owing to static electricity,they are required similarly to have an antistatic property.

As the method for providing articles, particularly synthetic resinmolded products, with the antistatic property are there a method ofadding a conductive filler such as a carbon black, a metal powder, and aconductive metal oxide, a surfactant to materials comprising thearticles and a method of forming an antistatic layer containing aconductive filler or an antistatic layer obtainable by a surfactant onthe article surface. However, the above-mentioned respective methods hadproblems. That is, with respect to the method of adding the conductivefiller to materials comprising the articles, a large quantity of theconductive filler had to be added to obtain a good antistatic propertyand accordingly there were the problems that the moldability of thearticles was deteriorated, the articles became opaque or it becamedifficult to colorize the articles with optional colors. Also, withrespect to the method of adding the surfactant to materials comprisingthe articles, there was a disadvantage that the conductivity was too lowto provide a sufficient antistatic property and the antistatic propertywas sensitive to ambient humidity.

Further, with respect to the method of forming an antistatic layercomprising the surfactant on the article surface, there was a problemthat the antistatic property was insufficient and the antistatic layercontaining the surfactant was eliminated by washing with water oralcohol and thus was easy to be removed by friction and lacks indurability.

On the other hand, as a method of forming the antistatic layercontaining the conductive filler on the article surface is there, forexample, a method of applying an antistatic coating material containingconductive metal oxide fine particles to the article surface. However,such a coating material containing a large quantity of fine particlesshowed a thixotropic property, so that the smooth coating formation wasinterfered and application to articles required to be transparent waslimited. That is, since coating had to be carried out by using a rollcoater or the like under strong shearing force application condition toimprove the surface smoothness and transparency and therefore thecoating method was limited and post-treatment such as buff polishing(reference to Japanese Kokoku Publication Sho-63-33778), specular hotpress (Japanese Kokoku Publication Hei-6-15071) had to be carried outadditionally after coating.

Additionally, these methods were effective for flat articles such asplate-like or film-like articles, however in the case of molded bodieshaving concave and convex parts, curved faces, or complicatedthree-dimensional shapes such as container-like shapes, coating by aroll coater while applying shearing force or post-treatment by buffpolishing or the like was difficult and consequently, no antistaticmolded body excellent in transparency, surface smoothness, anddurability had been made available so far.

Further, a method of press-molding or vacuum-molding a plate with theantistatic layer previously formed on the surface was generally employedas a method of producing an antistatic molded body with such acomplicated shape as described above, however there was a problem thatin the case of molding the plate with the antistatic layer formed on thesurface, the antistatic layer on the portion to be deformed could notfollow the deformation and therefore the antistatic property wasdeteriorated.

SUMMARY OF THE INVENTION

In view of the above-mentioned state of the art, it is the object of theinvention to provide an antistatic molded body excellent in anantistatic property obtained simply by applying an antistatic coatingmaterial to a substrate without deteriorating the surface smoothness,the transparency and coloration of the substrate and particularly toprovide an antistatic molded body comprising a substrate having concaveand convex parts, an three-dimensional complicated shape and anantistatic layer formed thereon.

It is also the object of the invention to provide an antistatic coatingmaterial excellent in transparency, surface smoothness, and antistaticproperty, easy to be applied, and unnecessary to be post-treated.

The invention is an antistatic molded body comprising an antistaticlayer comprising an antistatic coating material containing a conductivemetal oxide on the surface of a substrate and having a surfaceresistivity of 1×10⁴ to 1×10⁹ Ω/□ and the surface roughness (Ra) of 5 to50 nm.

The antistatic molded body of the invention is preferable to have a hazevalue of 10% or lower and a total light transmittance of 84% or higher.

The antistatic molded body of the invention is preferably athree-dimensional body having concave and convex parts.

The antistatic layer of the antistatic molded body of the invention ispreferable to be formed by simply spraying an antistatic coatingmaterial.

The antistatic coating material to be used for the antistatic moldedbody of the invention is preferably a coating material which contains aconductive metal oxide fine particle, a binder resin and an organicsolvent and in which a solid matter concentration is 1 to 20% by weight,a content of said conductive metal oxide fine particle in said solidmatter is 50 to 80% by weight, an average particle diameter of saidconductive metal oxide fine particle is 100 nm or smaller, and a contentof said conductive metal oxide fine particle with a particle diameter of200 nm or larger is 10% by weight or less.

The conductive metal oxide or the conductive metal oxide fine particleis preferably tin oxide.

The antistatic coating material preferably has the viscosity of 5 to 30cps.

Such an antistatic coating material is also one of the inventions.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the invention will be described in detail.

An antistatic molded body of the invention comprises an antistatic layercomprising an antistatic coating material containing a conductive metaloxide on the surface of a substrate.

The above-mentioned antistatic coating material is not particularlylimited, however, for example, a coating containing conductive metaloxide fine particles, a binder resin, and an organic solvent ispreferable to be used.

As the above-mentioned conductive metal oxide fine particles, tin oxidesuch as an antimony-containing conductive tin oxide and indium tin oxidecan be exemplified and particularly, antimony-containing conductive tinoxide is preferable. Also, as the above-mentioned conductive metal oxidefine particles, compounded fine particles obtained by forming aconductive metal oxide layer on the surface of transparent fineparticles can be employed. As such compounded fine particles, conductivefine particles obtained by forming a layer comprisingantimony-containing conductive tin oxide on the surface of fineparticles of barium sulfate are commercialized.

As the conductive metal oxide fine particles to be added to theabove-mentioned antistatic coating material, since it is required to befinely dispersed in the coating material, those having an averageparticle diameter of 100 nm or smaller, preferably 50 nm or smallerbefore addition to the coating material are preferable to be used. Theconductive metal oxide fine particles are dispersed in such a manner asthat an average particle diameter thereof is 100 nm or smaller in theabove-mentioned antistatic coating material and the content of particleswith particle diameter of 200 nm or larger is 10% by weight or less inthe total of the conductive metal oxide fine particles. In the case theaverage particle diameter of the conductive metal oxide fine particlesexceeds 100 nm or the content of the particles with a particle diameterof 200 nm or larger exceeds 10% by weight, the surface of the coatingfilm becomes rough and it is difficult to form an antistatic layer withan even thickness and smooth surface. Particularly, in the case thesubstrate is colored or transparent, if the obtained antistatic layer isopaque, the color of the obtained antistatic molded body becomes unclearor opaque. The average particle diameter of the conductive metal oxidefine particles in the above-mentioned antistatic coating material is avalue calculated by diluting the antistatic coating material with asolvent and subjecting the diluted material to a light scattering methodand an average particle diameter of particles including primaryparticles and agglomerates. The conductive metal oxide fine particleswith a particle diameter of 200 nm or larger also include agglomeratesformed by agglomeration of a plurality of primary particles. Morepreferable average particle diameter is 50 nm or smaller and morepreferable content of particles with a particle diameter of 200 nm orlarger is 5% by weight or less.

The content of the conductive metal oxide fine particles in theabove-mentioned antistatic coating material is preferably 50 to 80% byweight in the solid matter of the coating material. If it is less than50% by weight, the antistatic property is sometimes insufficient andeven if it is added more than 80% by weight, the antistatic property tobe obtained is not so sufficient as to correspond to the addition amountand further it becomes difficult to disperse the particles in such amanner of keeping the average particle diameter be 100 nm or smaller.

The above-mentioned binder resin is not particularly limited and resinssuch as vinyl chloride resin, polyester resin, acrylic resin, which arecommonly used as a binder for a lacquer type coating material, andreactive resins such as UV curable resin and thermosetting resin can beexemplified.

As the above-mentioned organic solvent, any solvents which dissolve theabove-mentioned binder resin and which do not interfere thedispersibility of the above-mentioned conductive metal oxide fineparticles may be used without any particular limitation and examples ofthe solvent include ketones such as methyl ethyl ketone, methyl isobutylketone, and cyclohexanone; acetic acid esters such as ethyl acetate andbutyl acetate; and aromatic hydrocarbon compounds such as toluene andxylene. These solvents may be selected properly corresponding to thetype of the binder resin and requirements of coating properties and theymay be used alone or two or more of them may be used in combination.

The solid matter concentration of the above-mentioned antistatic coatingmaterial is preferably 1 to 20% by weight. If it is less than 1% byweight, the adhesion amount of the coating material has to be large andaccordingly, the coating material is fluidized so much as to cause aproblem of dripping or the like. On the other hand, if it exceeds 20% byweight, thixotropic property is intensified and the coating film surfaceis roughened and no antistatic layer with an even thickness and smoothsurface can be obtained and particularly in the case of forming acoating by spray coating, the coating film surface is made concave andconvex by the splashes, and therefore the transparency of the antistaticlayer is deteriorated. Adjustment of the solid matter concentration tobe 1 to 20% by weight gives an antistatic layer which is transparent andhas a smooth surface can be obtained without requiring post-treatmentsuch as buff finishing or the like. The more preferable lower limit is5% by weight and the more preferable upper limit is 10% by weight. Theabove-mentioned solid matters mean mainly the above-mentioned binderresin and the above-mentioned conductive metal oxide fine particles.

The above-mentioned antistatic coating material is preferable to have aviscosity of 5 to 30 cps. If the viscosity is 5 to 30 cps, coating byspray coating becomes easy. In addition, the above-mentioned viscosityis a value measured by a B-model viscometer under conditions of 20° C.,rotor No. 2, and rotation speed 50 rpm.

Such an antistatic coating material is also one of the inventions.

The antistatic layer of the antistatic molded body of the invention is,for example, formed by applying the above-mentioned antistatic coatingmaterial to the substrate surface.

The method for applying the above-mentioned antistatic coating materialto the substrate surface is not particularly limited and, for example, amethod of using a brush, a spray method, a dipping method, a roll coatmethod, a bar code method, a doctor blade method and the like can beexemplified. In the case the substrate has a relatively simple shapejust like a plate, sheet, or film, any of the above exemplified coatingmethods can provide a good antistatic layer, however in the case thesubstrate is a three-dimensional body like a container-like shape havingcomplicated concave and convex parts, e.g. an concave and convex surfaceor curved face, the spray method is preferable to be employed. The spraymethod can make the thickness of the coating relatively easily uniformeven if the substrate has a complicated shape. Therefore, a coating witha uniform thickness can be obtained by the spray method and thus atransparent antistatic layer with a smooth surface can be formed only byspray coating of the antistatic coating material without requiringpost-treatment such as buff finishing.

The thickness of the above-mentioned antistatic layer is notparticularly limited, however, the thickness after drying the coating ispreferably 0.2 to 10 μm. If it is thinner than 0.2 μm, the smoothness ofthe surface of the antistatic layer is affected by the surface state ofthe substrate and becomes inferior, and therefore the antistaticproperty becomes insufficient. On the other hand, if it exceeds 10 μm,the transparency of the antistatic layer is deteriorated.

The substrate of the antistatic molded body of the invention is notparticularly limited and may include molded bodies obtainable bysynthetic resins including polyolefin resins such as polyethylene resinand polypropylene resin; thermoplastic resins such as vinyl chlorideresin, acrylic resin, polycarbonate resin, polystyrene resin, andpolyester resin such as polyethylene terephthalate; and thermosettingresins such as phenol resin and epoxy resin; and inorganic substancessuch as glass and they may be properly selected depending on the uses,however in terms of lightweight and moldability and the like, moldedbodies obtainable by synthetic resins are preferable.

The above-mentioned substrate may be plate-like or film-like state andif the substrate is a three-dimensional body having concave and convexparts such as curved faces and bent portions, the invention isparticularly suitable for using.

The molding method of the substrate is not particularly limited and, forexample, injection molding, vacuum molding, extrusion molding, and pressmolding can be exemplified.

The antistatic molded body of the invention has a surface resistivity of1×10⁴ to 1×10⁹ Ω/□. If it is lower than 1×10⁴ Ω/□, the antistaticproperty is not a problem, however depending on the use, theconductivity is so high as to cause undesirable incident such as devicebreakdown owing to electric discharge in the case of a container of asemiconductor device. On the other hand, if it exceeds 1×10⁹ Ω/□, theantistatic property becomes insufficient. In addition, theabove-mentioned surface resistivity is a value calculated according toJIS K 6911 and in the case the shape of the antistatic molded body ofthe invention is complicated, it can be calculated by measuring theresistance between electrodes by a high resistance measuring apparatusand converting the measured resistance into the surface resistivityvalue.

The surface roughness (Ra) of the antistatic molded body of theinvention is 5 to 50 nm. If it is lower than 5 nm, the post-treatmentsuch as surface finishing is required and if it exceeds 50 nm, there arethe problems that the transparency of the antistatic molded body isdeteriorated and no smooth surface can be obtained. In addition, theabove-mentioned surface roughness (Ra) is the arithmetic means roughnesscalculated according to JIS B 0601.

In the case the antistatic molded body of the invention is required tobe transparent, the haze value is preferably 10% or lower. If it exceeds10%, the transparency of the antistatic molded body is deteriorated. Amore preferable upper limit is 5%. The haze value of the antistaticmolded body of the invention is affected by the haze value of thesubstrate itself, however in a typical example of the invention, thehaze value of the antistatic molded body of the invention is suppressedto be higher than that of the substrate by at most 3%. In addition, thehaze value is a value calculated according to JIS K7105.

The antistatic molded body of the invention is preferable to have atotal light transmittance of 84% or higher. If it is less than 84%,depending on the uses, the transparency of the antistatic molded body isinsufficient. To make the total light transmittance 84% or higher, amolded body obtainable by transparent resin such as acrylic resin, e.g.PMMA and polycarbonate resin, e.g. PC is preferable to be used as thesubstrate. The total light transmittance of the antistatic molded bodyis also affected by the total light transmittance of the substratesimilarly to the haze value and the decrease of it can be suppressedwithin 10% of the total light transmittance of the substrate in atypical example of the invention. In addition, the above-mentioned totallight transmittance can be a value calculated according to JIS K 7105,similarly to the haze value.

The use of the antistatic molded body of the invention is notparticularly limited, however, for example, it is used preferably for awafer container, a photomask container, a door and cover of a precisionproduction apparatus of a semiconductor, a luminaire cover.

Conventionally, in the case of applying a coating material containingconductive metal oxide fine particles dispersed therein particularly bya spray method, it is generally difficult to obtain a transparentcoating with smooth surface. The reasons for that are supposed asfollows.

The first reason is that the particle diameter of the agglomerates ofthe conductive metal oxide fine particles is large. The conductive metaloxide fine particles with an average particle diameter of primaryparticles of several ten nm are used for a transparent antistaticcoating material, however it is very difficult to disperse theabove-mentioned conductive metal oxide fine particles in primaryparticle state and in general, the particles exist in form ofagglomerates formed by agglomeration of a large number of primaryparticles. If the particle diameter of the above-mentioned agglomeratesis large, since light scattering is increased and the coating surfacebecomes concave and convex, it is impossible to obtain a transparent andsmooth coating. Further, in the case of spray coating, splashes arebrought into contact fiercely with air while flying in air, and thecoating material is deprived of the evaporation latent heat and absorbsmoisture, and attributed to that, further larger agglomerates of theconductive metal oxide fine particles are produced and accordingly thetransparency and smoothness of the coating tend to be deteriorated.

The second reason is because the sprayed splashes are adhered on thesubstrate surface and dried and solidified before being sufficientlyleveled and therefore concave and convex traces of the splashes are lefton the coating surface. It occurs commonly in spray coating that thetraces of splashes are easy to remain on the coating surface, howeverthe tendency is significant in the case of the antistatic coatingmaterial containing a large quantity of the conductive metal oxide fineparticles. The reason for that is supposed because the coating materialhas a thixotropic property.

To deal with that problem, in the invention, the solid matterconcentration in the antistatic coating material is suppressed to lowand the conductive metal oxide fine particles with an average particlediameter of 100 nm or smaller and containing particles with a particlediameter of 200 nm or larger in a content of 10% by weight or less areused in the antistatic coating material and thus the antistatic layerwith excellent transparency and surface smoothness can be formed on asubstrate by simply spray coating without requiring post-treatment.

BEST MODES OF THE EMBODIMENTS OF THE INVENTION

The invention will be described in further detail by way of Examples,but is not limited by these Examples.

EXAMPLE 1

[Production of Substrate]

A 2 mm-thick transparent acrylic plate was formed into a bowl-like shapewith a curvature radius of 10 cm by a vacuum molding method. The hazevalue of the substrate itself of the transparent acrylic resin was 3%and the total light transmittance was 91% after molding.

[Production of Antistatic Coating Material]

A bead mill filled with beads having a diameter of 0.3 mm and made ofzirconia was filled with cyclohexanone 63 parts by weight and a vinylchloride copolymer (trade name: MR-110, manufactured by ZEONCorporation) 14 parts by weight, rotated at a rotation speed of 100 rpmfor 10 minutes and then the vinyl chloride copolymer was dissolved inthe solvent. After that, an antimony-doped tin oxide powder (trade name:T-1; manufactured by Mitsubishi Materials Corporation; primary particlediameter 20 nm) 23 parts by weight was added little by little. After theaddition, the rotation speed was increased to 2,300 rpm and the mixturewas stirred for 4 hours to obtain a raw solution of an antistaticcoating material. The obtained coating material raw solution was dilutedwith cyclohexanone and then an antistatic coating material with a solidmatter concentration of 10% by weight was obtained.

[Application to the Substrate]

The diluted coating material was applied to the above-mentionedsubstrate by spray coating so as to adjust the average coating amount of40 g/m² and dried at 60° C. for 20 minutes by hot air blow to obtain anantistatic molded body.

EXAMPLE 2

An antistatic molded body was obtained in the same manner as Example 1,except that the solid matter concentration of the coating material wasadjusted to be 3% by weight and the coating amount was changed to 100g/m².

EXAMPLE 3

An antistatic molded body was obtained in the same manner as Example 1,except that the addition amount of the vinyl chloride copolymer was 12parts by weight, the addition amount of the antimony-doped tin oxidepowder was 25 parts by weight, the solid matter concentration of thecoating material was adjusted to be 5% by weight, and the coating amountof the coating material was changed to 80 g/m².

EXAMPLE 4

An antistatic molded body was obtained in the same manner as Example 1,except that the stirring time at a rotation speed of 2,300 rpm wasprolonged to 7 hours.

COMPARATIVE EXAMPLE 1

[Production of Antistatic Coating Material]

An antistatic coating material was produced in the same manner asExample 1, except that the stirring time at a rotation speed of 2,300rpm was shortened to 30 minutes.

[Application to the Substrate]

After the antistatic molded body was produced in the same manner asExample 1, buff finishing was carried out as the post-treatment.

COMPARATIVE EXAMPLE 2

An antistatic molded body was obtained in the same manner as Example 1,except that the solid matter concentration of the coating material wasadjusted to be 30% by weight.

COMPARATIVE EXAMPLE 3

An antistatic molded body was obtained in the same manner as ComparativeExample 1, except that the buff finishing was not carried out.

[Evaluation]

The antistatic coating materials and the antistatic molded bodiesobtained in the respective Examples and Comparative Examples wereevaluated for the following items. The results are shown in Table 1.

(Particle Diameter of Tin Oxide Fine Particles)

Each antistatic coating material was diluted with methyl ethyl ketoneand the particle diameter was measured by a particle distribution meter(HORIBA LA-910, manufactured by HORIBA SEISAKUSHO CO., Ltd.) by a laserscattering method.

(Surface Resistivity)

Resistance was measured at 5 points of the surface of each antistaticmolded body by a high resistance meter (TR-3; manufactured by TOKYOELECTRONICS CO., LTD.) and then surface resistivity was calculated. Itsrange is shown in Table 1.

(Surface Roughness (Ra)) The surface roughness (Ra) of each antistaticmolded body was calculated by a surface shape measurement apparatus(SURFCOM 480, manufactured by TOKYO SEIMITSU CO., LTD.).

(Haze Value and Total Light Transmittance)

A specimen with 5 cm×10 cm size was cut off from each antistatic moldedbody and subjected to the haze value and total light transmittancemeasurements for the antistatic molded body by a haze meter (ND-1001DP,manufactured by Nippon Denshoku Industries Co., Ltd.)

(Viscosity of Coating Material)

Viscosity was measured at 20° C. and on the condition of a rotationspeed of 50 rpm with a rotor No. 2 by a B-type viscometer (B 8 H,manufactured by Tokyo Keiki Co., Ltd.). TABLE 1 Comparative ComparativeComparative Example 1 Example 2 Example 3 Example 4 Example 1 Example 2Example 3 Solid matter concentration (in coating wt. % 10 3 5 5 10 30 10material) Tin oxide content (in solid matters) wt. % 62 62 68 68 62 6262 Tin oxide average particle diameter nm 90 90 92 70 180 90 180dispersion state content of particles with wt. % 7 7 8 3 35 7 35particle diameter of 200 nm or larger Viscosity of antistatic coatingmaterial cps 25 12 16 20 22 147 22 Performance of buff finishing nonenone none none done none none Evaluation surface resisitivity × 10⁶ Ω/□20˜80 40˜90 3˜6 40˜90 3˜6 20˜80 3˜6 result surface roughness (Ra) nm 3530 39 32 5 777 65 haze value % 5 4 6 4 4 35 28 total light transmittance% 86 87 84 84 87 83 84Industrial Applicability

With the above-mentioned constitution, the invention provides anantistatic molded body excellent in the antistatic property,transparency, and surface smoothness obtainable by simply applying anantistatic coating material to a substrate without requiring additionalpost-treatment such as buff finishing even if the substrate has concaveand convex parts and complicated three-dimensional shape and theobtained antistatic molded body is preferably utilized for facilities,parts and the like to be used in clean rooms.

Use of the antistatic coating material of the invention makes itpossible to provide a coating excellent in the antistatic property,transparency, and surface smoothness by simply applying it to asubstrate by spray method or the like without requiring complicatedpost-treatment such as buff finishing and therefore is suitable for usefor preventing electrostatic charge for a molded body with a complicatedshape.

1. An antistatic molded body, which comprises an antistatic layercomprising an antistatic coating material containing a conductive metaloxide on a surface of a substrate and has a surface resistivity of 1×10⁴to 1×10⁹ Ω/□ and a surface roughness (Ra) of 5 to 50 nm.
 2. Theantistatic molded body according to claim 1, wherein a haze value is 10%or lower.
 3. The antistatic molded body according to claim 1, wherein atotal light transmittance is 84% or higher.
 4. The antistatic moldedbody according to claim 1, which is a three-dimensional body havingconcave and convex parts.
 5. The antistatic molded body according toclaim 1, wherein the antistatic layer is formed by simply spraying theantistatic coating material.
 6. The antistatic molded body according toclaim 1, wherein the conductive metal oxide is tin oxide.
 7. Theantistatic molded body according to claim 1, wherein the antistaticcoating material contains a conductive metal oxide fine particle, abinder resin and an organic solvent and has a solid matter concentrationof 1 to 20% by weight and said content of the conductive metal oxidefine particle in said solid matter of 50 to 80% by weight, an averageparticle diameter of said conductive metal oxide fine particle being 100nm or smaller, and a content of said conductive metal oxide fineparticle with a particle diameter of 200 nm or larger being 10% byweight or less.
 8. An antistatic coating material, which contains aconductive metal oxide fine particle, a binder resin and an organicsolvent and has a solid matter concentration of 1 to 20% by weight and acontent of said conductive metal oxide fine particle in said solidmatter of 50 to 80% by weight, an average particle diameter of saidconductive metal oxide fine particle being 100 nm or smaller, and acontent of said conductive metal oxide fine particle with a particlediameter of 200 nm or larger being 10% by weight or less.
 9. Theantistatic coating material according to claim 8, wherein the conductivemetal oxide fine particle is tin oxide.
 10. The antistatic coatingmaterial according to claim 8, which has a viscosity of 5 to 30 cps. 11.The antistatic molded body according to claim 2, wherein a total lighttransmittance is 84% or higher.
 12. The antistatic molded body accordingto claim 2, which is a three-dimensional body having concave and convexparts.
 13. The antistatic molded body according to claim 3, which is athree-dimensional body having concave and convex parts.
 14. Theantistatic molded body according to claim 2, wherein the antistaticlayer is formed by simply spraying the antistatic coating material. 15.The antistatic molded body according to claim 3, wherein the antistaticlayer is formed by simply spraying the antistatic coating material. 16.The antistatic molded body according to claim 4, wherein the antistaticlayer is formed by simply spraying the antistatic coating material. 17.The antistatic molded body according to claim 2, wherein the conductivemetal oxide is tin oxide.
 18. The antistatic molded body according toclaim 3, wherein the conductive metal oxide is tin oxide.
 19. Theantistatic molded body according to claim 4, wherein the conductivemetal oxide is tin oxide.
 20. The antistatic molded body according toclaim 5, wherein the conductive metal oxide is tin oxide.